A cup is a general term for a vessel intended to contain beverages or liquid foods for drinking or consumption.
A paper cup is a cup made out of paper and often lined with plastic or wax to prevent liquid from leaking out or soaking through the paper. It may be made of recycled paper and is widely used around the world. Paper cups can be made from virgin paper; cups made from recycled content are limited to 10% recycled content by law.
Originally, paper cups for hot drinks were glued together and made waterproof by dropping a small amount of clay in the bottom of the cup, and then spinning at high speed so that clay would travel up the walls of the cup, making the paper water-resistant. However, this resulted in drinks smelling and tasting of cardboard.
Cups for cold drinks could not be treated in the same way, as condensation forms on the outside, then soaks into the board, making the cup unstable. To remedy this, cup manufacturers developed the technique of spraying both the inside and outside of the cup with wax. Both clay-coated and wax-coated cups disappeared with the invention of polyethylene (PE) coated cups; this process covers the surface of the board with a very thin layer of PE, not only waterproofing the board, but also allowing seams to be welded together. The waterproof PE lining makes it difficult to easily recycle paper coffee cups and renders cold drink cups unrecyclable. There are a few paper mills that will accept small quantities of hot drink cups for recycling.
Most paper cups are designed for a single use and then disposal or recycling. All cups have the following in common:
A bottom
Sidewall(s) attached to the bottom
An large opening at the top for filling and drinking sometime covered with a lid
Made from a material that will hold liquid for the life of use
Rigid enough to be picked up in one hand for carrying and consumption
Rigid enough to have a lid pressed on
Many cupped beverages are sold and consumed away from home and many beverages cupped at home are consumed away from home.
The advantage of selling and consuming beverages away from home and the inconvenience of returning or cleaning the cups after use has led to the widespread use of disposable cups. In order for these disposable cups to meet the minimum requirements they must both have significant strength for grasping and carrying and an inner surface that is impervious to the liquid and in the case of cold drinks an exterior surface impervious to accumulation of condensation during the life of use.
Since the cupped beverages sold away from home are generally inconvenient for the return of the cup, paper or plastic cups are generally used and disposed of after a single use. These cups require a considerable amount of material for strength and a liquid impervious surface that renders them very difficult to biodegrade, compost or recycle.
Also in the case of single use hot drink cups a method of protecting the hand from high temperatures is often a requirement. Cups filled at home and taken away must be brought back into a building in almost all cases for cleaning. Another problem with paper cups is that the seam on the side and lip of the cup creates an area where liquid can leak out when the lid is in place.
Over 6.5 million trees were cut down to make 16 billion paper cups used by US consumers in 2006, using 4 billion gallons of water and resulting in 253 million pounds of waste.
Very little recycled paper is used to make paper cups because of contamination concerns and regulations. Because most paper cups are coated with plastic, both composting and recycling of paper cups is uncommon.
Although paper cups are made from renewable resources (wood chips 95% by weight), paper products in a landfill may not decompose, or may release methane if decomposed anaerobically. The manufacture of paper usually requires inorganic chemicals and creates water effluents.
Paper cups may consume more non-renewable resources than cups made of polystyrene foam. A number of cities have banned XPS foam cups in take-out and fast food restaurants.
PE is a petroleum based coating on paper cups that can slow down the process of biodegrading. PLA is a biodegradable bio-plastic coating used on some paper cups. PLA is a renewable resource and makes paper cups more compostable, whereas PE is not renewable and is not compostable.
Traditionally paper cup and containers have a plastic liner adhered to the inside in order to make them waterproof. These liners cannot be easily separated from the paper at the end of the life of the container and the paper cup/containers are not designed to be washed, they are for single use only and therefore cannot be reused. Some efforts to recycle the hot-beverage paper container have been successful however this requires additional energy and significant fiber loss, also very few paper mills are equipped to handle this type of recycled material. Additionally the paper cup/containers with the plastic liners do not biodegrade completely and don not compost easily. Permanent cup/containers require washing between used that requires the use of hot water and soap.
The pervasiveness of coffee-to-go from coffee shops, fast food venues and restaurants has exacerbated the problem of recycling the portable single-use cups. An increasing number of environmentally conscious consumers are demanding that these establishments proactively tackle recycling and waste reduction. Initiatives to decrease the environmental impact of disposable cups include using a recycled-content cup sleeve instead of double-cupping; producing hot beverage cups with 10% post-consumer recycled fiber, and offering a discount to consumers to use their own reusable mugs or tumblers for their beverages.
In many communities, there is a dearth of commercial recycling facilities. Until this situation improves front-of-store recycling that is consumer friendly is needed. This effort will be a combination of new cup design, convenient collection, and recycling infrastructure. However developing recyclable cup solutions is vital.
A need exists to have a cup/container in which a plastic liner could be removed so that both the cup/container and liner can be recycled and the cup/container can biodegrade. In addition, a need exists with a permanent cup/container for the liner to be removed, thus eliminating the need to wash the cup/container.
Yet another need is to minimize manual assembly by having a machine to uniformly insert a liner into the cup/container and assist in the fitting of the liner snugly to the inside and outside of the cup/container. The liners need to be manufactured and configured to seamlessly feed into this machine and fit on the target cup, e.g. by a stretch-fit and/or shrink-fit process.
Related patents and published patent applications known in the background art include the following:    U.S. Pat. No. 3,373,917, issued to Cox on Mar. 19, 1968, discloses a foldable container;    U.S. Pat. No. 4,391,366, issued to Hirata on Jul. 5, 1983, discloses a foldable cup;    U.S. Pat. No. 6,458,067, issued to Dorin et al. on Oct. 1, 2002, discloses removable conformal liners for centrifuge containers;    U.S. Pat. No. 4,036,675, issued to Amberg et al. on Jul. 19, 1977, discloses film-lined foam plastic receptacles and laminated materials and methods for making the same;    U.S. Pat. No. 4,854,474, issued to Murray et al. on Aug. 8, 1989, discloses a composite drinking cup;    U.S. Pat. No. 6,889,455, issued to Giraud on May 10, 2005, discloses a method of incorporating a promotional item into a dual wall cup;    U.S. Pat. No. 7,513,386, issued to Hartjes et al. on Apr. 7, 2009, discloses a container employing an inner liner for thermal insulation;    U.S. Patent Application Publication No. 2010/0038361, filed by Hwang and published on Feb. 18, 2010, discloses a disposable cup which may be used as packing material and manufacturing method of the same; and    International application WO 99/49770, filed by Miller et al. and published on Oct. 7, 1999 discloses a flushable potty liner.
The foregoing patent information reflects the state of the art of which the inventor is aware and is tendered with a view toward discharging the inventor's acknowledged duty of candor in disclosing information that may be pertinent to the patentability of the technology described herein. It is respectfully stipulated, however, that the foregoing patent and other information do not teach or render obvious, singly or when considered in combination, the inventor's claimed invention.